1. Field of the Invention
This invention generally relates to regenerative cells derived from a wide variety of tissues, and more particularly, to adipose-derived regenerative cells (e.g., stem and/or progenitor cells), methods of using adipose-derived regenerative cells, compositions containing adipose-derived regenerative cells, and systems for preparing and using adipose-derived regenerative cells which are used to treat musculoskeletal diseases and disorders, e.g., spine, tendon, ligament, cartilage, skeletal muscle, and bone related diseases and disorders.
2. Description of Related Art
Musculoskeletal disorders are a large group of common diseases and disorders which can involve bone, muscles, ligaments, tendons, cartilage and joints. Musculoskeletal disorders occur frequently and include non-specific complaints such as back pain, neck pain or repetitive strain injury, chronic inflammatory or degenerative rheumatic disorders as well as a wide range of other sports injuries and work-related injuries. Apart from the personal suffering endured by patients, musculoskeletal disorders cause substantial social economic problems because of the high costs incurred by work absenteeism and work disability. Musculoskeletal disorders are one of the main reasons for which patients visit their general practitioner. In fact, the Bureau of Labor Statistics recently reported that one half of the 2.3 million nonfatal occupational injuries and illnesses which resulted in days away from work involved musculoskeletal disorders. These disorders account for more than thirty-four percent of all workdays lost to injuries and illnesses and cost employers $15 to $20 billion per year in direct workers compensation costs and another $100 billion on lost productivity, employee turnover, and other indirect expenses.
Examples of musculoskeletal disorders include: sprains, strains, tendonitis, tenosynovitis, fibromyalgia, osteoarthritis, rheumatoid arthritis, polymyalgia rheumatica, bursitis, acute and chronic back pain and osteoporosis. Sports and work related injuries include sprains, strains and tears of ligaments, tendons, muscles and cartilage. Pain is the most common symptom and is frequently caused by injury or inflammation. Besides pain, other symptoms such as stiffness, tenderness, weakness and swelling or deformity of affected parts are manifestations of musculoskeletal disorders.
Currently, non-surgical methods for treating musculoskeletal injuries, including strain and sprain injuries to muscle, tendon and fascial components, are limited to drug therapy to mask pain during the healing process, immobilization, and various physiotherapies which often have limited success. No known methods currently exist to treat the injury and associated pain by accelerating the healing process itself. Surgical intervention for advanced disease states is a widely used option. Current surgical methods, however, generally require the use of autogenous bone (bone from the patient) or allograft bone (bone from another individual) to induce bone or cartilage formation. Autogenous bone is generally considered superior at promoting fusion. However, this procedure requires extra surgery to remove bone from another area of the patient's body such as the pelvis or fibula. Thus, it has been reported that about 30 percent of patients have significant pain and tenderness at the graft harvest site, which may be prolonged, and in some cases outlast the back pain the procedure intended to correct. Similarly, allograft bone and other bone graft substitutes, although eliminating the need for a second surgery, have drawbacks in that they have yet to be proven as cost effective and efficacious substitutes for autogenous bone fusion. Similarly, the use of growth factors that promote bone formation, e.g., bone morphogenic proteins (“BMPs”), has not proven cost-effective.
Given the aging of the population and unhealthy life-styles, it is anticipated that the incidence and prevalence of musculoskeletal disorders will increase substantially in the near future. Accordingly, regenerative medicine, which harnesses the ability of regenerative cells, e.g., stem cells and progenitor cells, to renew themselves indefinitely and develop into mature specialized cells, provides a promising new approach for treating musculoskeletal disorders.